Iron and cobalt complexes [Fe(RSO2N)2CO·H2O]n and [Co(RSO2N)2CO·1/2H2O]n which are deficient of terminal and bridging metal carbonyls have been isolates from the reaction of methane-, benzene-, and p-toluenesulfonyl azide with iron pentacarbonyl, diiron nonacarbonyl, and dicobalt octacarbonyl. Hydrolysis of these with dilute hydrochloric acid leads to the corresponding N,N′-bis(sulfonyl)urea. Possible structures for the complexes involving coordination of a sulfonyl oxygen to the metal are presented and supporting evidence for such coordination is given. Free singlet sulfonyl nitrenes are not formed in these decompositions. The decomposition of tert-butyl azidoformate with iron pentacarbonyl and diiron nonacarbonyl gave impure complexes, still containing terminal and bridging carbonyls, which could be hydrolyzed to give mainly tert-butyl carbamate, di-tert-butyl iminodicarboxylate, and N,N′-bis(tert-butoxycarbonyl)urea. © 1974, American Chemical Society. All rights reserved.